Lattice length for Zincblende structures

In summary, the conversation discusses the covalent radii of Ga and As, the structure of zinc blende, and a formula for calculating the distance between atoms in a crystal lattice. The formula, [4/sqrt(3)] x [ radius of Ga + radius of As ], can be used to calculate the distance of 5.66 A, but the reasoning behind it is unknown. It is also mentioned that the formula is similar to that of body-centered cubic packing, but it is unclear if there is any correlation between the two. The speaker suggests using simple geometry to calculate such distances.
  • #1
nefizseal
4
0
So we have the covalent Radii of Ga = 1.26 A and As = 1.19 A. And the structure is Zinc blende with arsenic occupying half of the tetrahedral sites. So its probably not close packed...

The formula the works for me is, [4/sqrt(3)] x [ radius of Ga + radius of As ]. I can get the answer ( 5.66 A ) by this but I don't know why or how it works? Can someone please explain the reasoning behind it.

Also I noticed this is like the formula for the Body centre cubic packing. Is there any corelation?
thx...
 
Chemistry news on Phys.org
  • #2
Without looking at the structure - such things can be always calculated just by simple geometry. Draw the cell, assume atoms "touch" each other, draw distances between atom centers, use whatever is needed to solve the triangles present.
 

Similar threads

What is the lattice constant of a zincblende structure with two types of atoms?
Replies
4
Views
2K
What is the method for calculating ion radii in a NaCl structure?
Replies
6
Views
3K
Textbooks on Condensed Matter Physics
Replies
19
Views
18K

Hot Threads

Recent Insights

Back
Top